export const Base64 = {

		// private property
		_keyStr: "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",

		// public method for encoding
		encode: function(input) {
			var output = "";
			var chr1, chr2, chr3, enc1, enc2, enc3, enc4;
			var i = 0;

			input = Base64._utf8_encode(input);

			while (i < input.length) {

				chr1 = input.charCodeAt(i++);
				chr2 = input.charCodeAt(i++);
				chr3 = input.charCodeAt(i++);

				enc1 = chr1 >> 2;
				enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
				enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
				enc4 = chr3 & 63;

				if (isNaN(chr2)) {
					enc3 = enc4 = 64;
				} else if (isNaN(chr3)) {
					enc4 = 64;
				}

				output = output +
					this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) +
					this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4);

			}

			return output;
		},

		// public method for decoding
		decode: function(input) {
			var output = "";
			var chr1, chr2, chr3;
			var enc1, enc2, enc3, enc4;
			var i = 0;

			input = input.replace(/[^A-Za-z0-9+/=]/g, "");

			while (i < input.length) {

				enc1 = this._keyStr.indexOf(input.charAt(i++));
				enc2 = this._keyStr.indexOf(input.charAt(i++));
				enc3 = this._keyStr.indexOf(input.charAt(i++));
				enc4 = this._keyStr.indexOf(input.charAt(i++));

				chr1 = (enc1 << 2) | (enc2 >> 4);
				chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
				chr3 = ((enc3 & 3) << 6) | enc4;

				output = output + String.fromCharCode(chr1);

				if (enc3 != 64) {
					output = output + String.fromCharCode(chr2);
				}
				if (enc4 != 64) {
					output = output + String.fromCharCode(chr3);
				}

			}

			output = Base64._utf8_decode(output);

			return output;

		},

		// private method for UTF-8 encoding
		_utf8_encode: function(string) {
			string = string.replace(/ /g, "");
					var utftext = "";

					for (var n = 0; n < string.length; n++) {

						var c = string.charCodeAt(n);

						if (c < 128) {
							utftext += String.fromCharCode(c);
						} else if ((c > 127) && (c < 2048)) {
							utftext += String.fromCharCode((c >> 6) | 192);
							utftext += String.fromCharCode((c & 63) | 128);
						} else {
							utftext += String.fromCharCode((c >> 12) | 224);
							utftext += String.fromCharCode(((c >> 6) & 63) | 128);
							utftext += String.fromCharCode((c & 63) | 128);
						}

					}

					return utftext;
				},

				// private method for UTF-8 decoding
				_utf8_decode: function(utftext) {
					var string = "";
					var i = 0;
					var c = c1 = c2 = 0;

					while (i < utftext.length) {

						c = utftext.charCodeAt(i);

						if (c < 128) {
							string += String.fromCharCode(c);
							i++;
						} else if ((c > 191) && (c < 224)) {
							c2 = utftext.charCodeAt(i + 1);
							string += String.fromCharCode(((c & 31) << 6) | (c2 & 63));
							i += 2;
						} else {
							c2 = utftext.charCodeAt(i + 1);
							c3 = utftext.charCodeAt(i + 2);
							string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));
							i += 3;
						}

					}

					return string;
				}

		}
